Jack



Oct. 12 1926.

v c. E. BElLHARZ Filed o'i Patented Oct. 12, 1926.

- GNI-TED: sTATi-is- QFFICE.

GAEL E. BEILHABZ, OF JOLIET, ILLINOIS ASSIGN O R TOiWIL LIAM E. PRATT MFG. CO.

i JACK.

Application fil'ed October This invention relates to litting jacks and has special reference to a litting jack of the pawl and ratchet type.

One in'portant Object ot the inventionis to improve the general construction of devices'o't this character.

A. second inportant Object of the invention is to provide an improved jael: of this type wherein the jack inay be used for raising an Object by a step-by-step novement and inay be loweredby a `siinilar niovernen novel neansbeing used to el'l'ect the*transition from a littingto a lowering j'aek.

A third Object of the invention is to provide a novel arrangenent of pawl controlling nechanisn in a jaok of'this description.

l'Vith the above and other objects in view as will be hereinatter' apparent, the invention consists' in general of certain novel details of 'construction and -c'onbinations of parts hereina'lter fully described, illnstrated in the accompanying drawings andspeeifi- @ally olaimed. v

In the acconpanying drawings-like char acters of 'reference indicate like parts in the several Views, and:

Figure 1 is side elevation of the complete jack. W p

' Figure 2 is a section taken on a -horizontal plane slightly above the standard:

Figure ?'is an enlarged side elevation of the working parts renioved from the jack and 'showing the same in litting position.

Figure %L is an edge View from the lett hand side of Figure 3, the ratchet bar-being omitted. v

Figure' 5`is a side elevation showing' the pawl controlling nieehanisn r in lowering position.

Figure 6 is a view of the pawls and ratchet showing their positions -in lowering an'object with the operating-handle fully raised.

This jack comprises a base IO having an upstanding casing llprovided atone side with' a guide channel wherein is mounted for vertical sl-iding movenent a ratchet bar'12 having ratched teeth 13 on its rear edge and' pre'terably provided with arotatable head lh 5, 1925. Serial No; 60,528.

arms l a retaining pawl. 19` is pivotally nounted on the bolt 15 and is provided with a downwardlyextending tail'20, the pawi being arranged to engage the ratchet teeth 13. Also there extends between the forward ends of said arms a pivot pin 21 and on this pin is nrounted an -actuating pawl haing a downwardly* extending tail 23 and likewi'se adapted to engage said ratchet teeth 13.

Mounted on a pivot bolt'24 between the sides of the frame 11 is an arin 25 carrying.

,lug 28 as a: limit stop in the opposite directiont On each pawl is a pin 29 and at 30 is a coiled torsion spring. having its 'arms 31 p ivotally secured to these-pins 29.

In' operation when it is 'desired to lift an. Object the jaok is placed thereunderand the lever 27 swung forwardlyiagainst the stop 28. This rotates thecam shaft so as to bring the high part of the can against the arn 25, thus forcing thesame rearwardly and: bringing the Springs 26 into -forcible en-* gagement .withthetails of the' pawls. This causes both pawls to engage the ratchet teeth; Upon-*depression of the handle 18 the pawl i 22IW1ll be raised and lift the ratched bar' untilhthepawl 191 engages beneath the ratched tooth next lower to that with whichait was formerly engaged. By repeatedly' oscillating the handle theratchet bar may'be protruded to, any desiredj extent within the limits of thelift of the jacl In case it 'is -wished to lower the Object 'and retract the ratehet bar the lever 27 is swung rearwardly intocontact with the head of the bolt 24. In this' Condition i the arm 25 swings forwardly and the Springs 26 assume thepositi ons shown in Figure (i, being tree from tlletals of thepawls; If, under these circumstances, the handle 18` be depressed the pawl 22" will first move' into engagement with atooth of the iratchet, this notionbeing caused bythe springO and its arms 31 whichact as a 'link between the pins 29` As soon as this is engaged a slight further depression of the lever tensions the spring 30 and at the same time liftsthe ratchet bar suihciently to free the pawl 19 which, due to the tension of the spring 30, is forced rearwardly. The handle 18 is then allowed to rise th'as lowering the ratchet bar. The spring and its arms now acts as a link to pnll the pawl 19 forwardly into engageinent below the tooth next above that with which it *formerly engaged. As the upward movement of the handle 18 is continued the pawl 22 is pnlled, by the spring 30, rearwardly and the pawls resume their initial position. Repetition ott the handle movement effects a step-by-step lowering.

There has thus been provided a simple and eflicient device of the kind described and for the purpose specified.

It is Obvious that minor changes may be made in the form and construction of the invention without departing from the material spirit thereof. It is not, therefore, desired to confine the invention to the exact form herein shown and described, bnt it is desired to include all such as properly come within the scope claimed.

Having thns described the invention, what is claimed as new,'is:

1. In a jack, a casing, a ratchet bar pro- 'trndable from the casing, an operating lever pivoted to said casing, a retaining pawl monnted concentrically with the pivot point of the lever and engageable with said ratchet, an operating pawl pivoted to said lever in spaced relation to its pivoted aXis and engageable with said ratchet, a spring link connecting said pawls, said spring link comprising a spiral spring having its ends angularly disposed, stnds located on said pawls adjacent the ratchetengaging ends thereof to which the ends of the sprial spring are connected, a pair o'lt' Springs movable into and out of contact with said pawls, and arranged when in contact to force said pawls into engagement with the ratchet, and releasable means to force said Springs into contact with said pawls.

2. In a jack, a casing, a ratchet bar protrndable from the casing, an operating lever pivoted to said casing, a retaining pawl mounted concentrically with the pivot point ot the lever and engageable with said ratchet, an operating pawl pivoted to said lever in spaced relation to its pivoted aXis and engageable with said ratchet, a spring link Connecting said pawls, said spring link comprising a spiral spring having its ends angularly disposed, stnds located on said pawls adjacent the ratchet engaging ends thereo'f to which the ends of the spiral spring are connected, a tail depending from each ot said pawls, a pair of Springs movable into and out of contact.with said tails and arranged when in contact to force said pawls into engagement with the ratchet, and reieasable means to :force said springs into contact with said tails.

8. In a jack, a casing, a ratchet bar protrudable from the casing, an operating lever pivoted to said casing, a. retaining pawl mounted concentrically with the pivot point of the lever and engageable with said ratchet, an operating pawl pivoted to said lever in spaced relation to its pivoted aXis and engageable with said ratchet, a spring link Connecting said pawls, said spring link comprising a spiral spring having its ends angularly disposed, studs located on said pawls adjacent the ratchet engaging ends thereot to which the ends of the spiral spring are connected, a tail depending from each et said pawls, an arm pivoted in said casing, a cam shaft having a cam with which said arn engages, means exterior. of the casing to rotate said cam shatt and thereby move said arn, and a pair oi" Springs each engaging a respective tail, said springs being carried by said arm and adapted upon movement ot the cam to one position to force the pawls into engagement with the ratchet and upon move- 'nent of the cam to a second position to allow said pawls to move 'treely for disengagement from the ratchet.

4. In a jack, a casing, a ratchet bar protrudable from the casing, an operating lever pivoted to said casing, a retaining pawl mounted concentrically with the pivot point of the lever and engageable with said ratchet, an operating pawl pivoted to said lever in spaced 'relation to its pivoted axis and engageable with said ratchet, a spring link connecting said pawls, a tail depending 'from each of said pawls, an arm pivoted in said casing, a cam sha'ft having a flat portion thereon with which said arm is adapted to engage when the cam shaft is rotated to one position, means exterior ot the casing to rotate said cam shatt to bring the round portion of the shaft into engagement with and thereby move said arm, a pair of springs each engaging respective tail, said Springs being carried by said arm and adapted npon movement ot the can to one position to force the pawls into engagement with the ratchet and npon movement of the cam to a second position to allow said pawls to move 'freely for disengagement from the ratchet, a stnd projeeting laterally from each pawl adjacent the nose thereot, and a spiral spring having one end connected to one stnd and the other to the other stnd and being 'free for movement in its central portion.

In testimony whereof I athx my signature.

GAEL E. BEILHARV. 

